<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div>Alec,</div><div id="AppleMailSignature">yes went off tangent there. Morning in NZ recovering from Christmas.</div><div id="AppleMailSignature">Alan</div><div id="AppleMailSignature"><br><br>Sent from my iPad</div><div><br>On 26/12/2017, at 10:08 AM, Alec Smyth via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br><br></div><blockquote type="cite"><div><div dir="ltr">Hi Alan,<div><br></div><div>Just to clarify, I was referring to HP Oxygen. For air I do bring HP into the hull and there is a 1st stage inside for the BIBS. </div><div><br></div><div>Thanks,</div><div>Alec</div></div><div class="gmail_extra"><br><div class="gmail_quote">On Mon, Dec 25, 2017 at 3:28 PM, Alan via Personal_Submersibles <span dir="ltr"><<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="auto"><div>Steve,</div><div id="m_320450563324451741AppleMailSignature">another factor that may influence your decision is how you want to </div><div id="m_320450563324451741AppleMailSignature">set up a BIBS. If you have a divers regulator for emergency breathing they</div><div id="m_320450563324451741AppleMailSignature">normally operate off 130 psi. Hmmm got me thinking now; if the emergency</div><div id="m_320450563324451741AppleMailSignature">regulator is operating off a line directly from the 1st stage regulator external</div><div id="m_320450563324451741AppleMailSignature">to the hull then it will see 130 psi above ambient. So at your max depth it will </div><div id="m_320450563324451741AppleMailSignature">see 255 psi.</div><div id="m_320450563324451741AppleMailSignature">Conversely if you had a high pressure line to your sub & a regulator dropping</div><div id="m_320450563324451741AppleMailSignature">the pressure to 130psi, then if you needed to flood your sub to get out the </div><div id="m_320450563324451741AppleMailSignature">regulator would only see 5 psi above ambient by the time the sub filled, if you </div><div id="m_320450563324451741AppleMailSignature">were escaping from 250ft.</div><span class=""><div id="m_320450563324451741AppleMailSignature">Alan</div><div id="m_320450563324451741AppleMailSignature"><br>Sent from my iPad</div></span><div><div class="h5"><div><br>On 26/12/2017, at 8:56 AM, Alec Smyth via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.<wbr>org</a>> wrote:<br><br></div><blockquote type="cite"><div><div dir="ltr">Hi Steve,<div><br></div><div>I use a 1st stage outside the hull. As you say the flow regulator can handle the tank pressure, so it is not strictly necessary, but I do so as an extra safety precaution to avoid bringing high pressure O2 inside. If doing it again I would the reg directly on the tank, so that way all of the tubing would see only low pressure. </div><div><br></div><div>I'm using a 1st stage that is incredibly inexpensive ($60), but I'm delighted with the quality and what is a big plus for me, it's a particularly simple design. I've collected three of them by now, and not any problem at all.</div><div><br></div><div><a href="https://www.piranhadivemfg.com/item/Balance-Piston-Din-First-Stage--For-Pony--Stage-Bottles--Nitrox-Ready-11738" target="_blank">https://www.piranhadivemfg.<wbr>com/item/Balance-Piston-Din-<wbr>First-Stage--For-Pony--Stage-<wbr>Bottles--Nitrox-Ready-11738</a></div><div><br></div><div>I do my own oxygen cleaning on tubing and penetrators, but prefer to buy O2-clean regs and valves. You may notice this reg is advertised for Nitrox, not pure oxygen. I spoke to the owner of the business selling it, and he told me the cleaning and materials are identical for partial or full O2, but that they advertise it only for partial O2 use as a legal CYA. </div><div><br></div><div><br></div><div>Best,</div><div>Alec </div></div><div class="gmail_extra"><br><div class="gmail_quote">On Mon, Dec 25, 2017 at 12:50 PM, Steve McQueen via Personal_Submersibles <span dir="ltr"><<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.<wbr>org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div lang="EN-US" link="#0563C1" vlink="#954F72"><div class="m_320450563324451741m_-2808635498830269245WordSection1"><p class="MsoNormal">All, I am purchasing the system components for my K-250’s O2 system. I am not a SCUBA diver so I lack some experience with regulators. I am considering sealed/balanced options for the first stage regulator (it will create an intermediate pressure downstream of the O2 tank (located external of the hull). These get pricey and I don’t really want to overspend for options I do not need (sealed vs. not, balanced vs. unbalanced, O2 ready vs. needing cleaned).<u></u><u></u></p><p class="MsoNormal"><u></u> <u></u></p><p class="MsoNormal">A couple of questions:<u></u><u></u></p><ol style="margin-top:0in" start="1" type="1"><li class="m_320450563324451741m_-2808635498830269245MsoListParagraph" style="margin-left:0in">They sell regulators that are already suitable for 100% O2 use. How difficult to clean one that is not O2 ready?<u></u><u></u></li><li class="m_320450563324451741m_-2808635498830269245MsoListParagraph" style="margin-left:0in">The pediatric flow regulator (located in the hull) can directly handle the O2 tank pressure so I am wondering why we use the first stage regulators at all.<u></u><u></u></li><ol style="margin-top:0in" start="1" type="a"><li class="m_320450563324451741m_-2808635498830269245MsoListParagraph" style="margin-left:0in">I assume to remove as many HP leak sources from within the hull especially since it is 100% O2 (safety).<u></u><u></u></li></ol></ol><p class="MsoNormal"><u></u> <u></u></p><p class="MsoNormal">Thoughts/recommendations?<span class="m_320450563324451741HOEnZb"><font color="#888888"><u></u><u></u></font></span></p><span class="m_320450563324451741HOEnZb"><font color="#888888"><p class="MsoNormal"><u></u> <u></u></p><p class="MsoNormal">Steve<u></u><u></u></p><p class="MsoNormal"><u></u> <u></u></p></font></span></div></div><br>______________________________<wbr>_________________<br>
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